Interesting, I appear to have replied to the wrong thread..
I dont know about the refresh, but historicly (i.e. 7900 series) the CiscoIPPhoneExecute is for sending to the phone via an HTTP post, not as a reply to a GET. Not sure if this is relevant, but might explain why the phone is crashing (i.e. wasn't a tested scenario).
The XML parser in the 50x series phones does seem a little... sketchy at times.
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